SARG 2.3.6 pkg v.0.6.1 - Graph issue

Since the 2.3.6 update, I no longer have access to the graphs in my SARG reports. No png files are created in the report directory.
When I run sarg in the ssh console, here's the output :

/usr/local/sarg-reports(48): sarg
SARG: (info) No graphs available as sarg was not compiled with libgd. Set "graphs" to "no" in /usr/local/etc/sarg/sarg.conf to disable this warning
SARG: Records in file: 45820, reading: 100.00%
SARG: Successful report generated on /usr/local/sarg-reports/01May2013-07May2013

May 9 10:17:43 php: /pkg_edit.php: The command '/usr/local/bin/sarg -d date +%d/%m/%Y-date +%d/%m/%Y' returned exit code '139', the output was 'SARG: (info) No graphs available as sarg was not compiled with libgd. Set "graphs" to "no" in /usr/local/etc/sarg/sarg.conf to disable this warning SARG: Records in file: 6, reading: 0.00%^MSARG: Period covered by log files: 09/05/2013-09/05/2013'